A micropipette is one of the instruments that is usually used in science laboratories .Micropipette are used to accurately measure and dispense small volumes of liquid . The capacity of a micropipette can range from less 1µl to 1000µl (1ml) .There are glass pipettes , air displacement pipettes , and positive displacement pipettes . Mostly , the air displacement pipettes and positive displacement pipettes are used . Firstly , the piston is moved to the appropriate position when the volume is set . Next , when the operating button is pressed to the first stop , the piston is expelled the same volume of air as indicated on the volume setting . After immersing the tip into the liquid , the operating button is released. It is usually used for applications like DNA amplification techniques . When the operating button is pressed to the stop , the piston descends to the tip opening . After the tip is immersed into the liquid , the operating button is released . The plunger is then raised and a partial vacuum is created . This causes the liquid to enter the tip . When the operating button is pressed again , the piston descends , expelling the liquid from the tip.
We need to optimize volume range by selecting the correct volume pipette . We must work in the 35% to 100% volume range for best accuracy and precision . Besides that , the tip immersion angle also plays an important role . Nextly, the micrometer setting must be done using the correct technique . If filled , we should not lay the pipette down or hold more than 20º from vertical . Lastly , we should not twist the volume higher than the maximum for the pipette . We should always check and clean the shaft and piston on a regular basis . Next , we should always clean pipette if aerosol or splashing occurs without use of a filter tip